pbdZMQ (version 0.2-1)

Socket Functions: Socket Functions

Description

Socket functions

Usage

zmq.socket(ctx, type = .pbd_env$ZMQ.ST$REP)
zmq.close(socket)
zmq.bind(socket, endpoint, MC = .pbd_env$ZMQ.MC)
zmq.connect(socket, endpoint, MC = .pbd_env$ZMQ.MC)
zmq.disconnect(socket, endpoint, MC = .pbd_env$ZMQ.MC)
zmq.setsockopt(socket, option.name, option.value, MC = .pbd_env$ZMQ.MC)
zmq.getsockopt(socket, option.name, option.value, MC = .pbd_env$ZMQ.MC)

Arguments

ctx

a ZMQ context

type

a socket type

socket

a ZMQ socket

endpoint

a ZMQ socket endpoint

MC

a message control, see ZMQ.MC() for details

option.name

an option name to the socket

option.value

an option value to the option name

Value

• zmq.socket() returns an R external pointer (socket) generated by ZMQ C API pointing to a socket if successful, otherwise returns an R NULL and sets errno to the error value, see ZeroMQ manual for details.

  zmq.close() destroys the socket reference/pointer (socket) and returns 0 if successful, otherwise returns -1 and sets errno to the error value, see ZeroMQ manual for details.

  zmq.bind() binds the socket to specific endpoint and returns 0 if successful, otherwise returns -1 and sets errno to the error value, see ZeroMQ manual for details.

  zmq.connect() connects the socket to specific endpoint and returns 0 if successful, otherwise returns -1 and sets errno to the error value, see ZeroMQ manual for details.

  zmq.setsockopt() sets/changes the socket option and returns 0 if successful, otherwise returns -1 and sets errno to the error value, see ZeroMQ manual for details.

  zmq.getsockopt() returns the value of socket option, see ZeroMQ manual for details.

Details

zmq.socket() initials a ZMQ socket given a ZMQ context ctx and a socket type. See ZMQ.ST() for the possible values of type. ZMQ defines several patterns for the socket type and utilize them to communicate in different ways including request-reply, publish-subscribe, pipeline, exclusive pair, and naive patterns.

zmq.close() destroys the ZMQ socket.

zmq.bind() binds the socket to a local endpoint and then accepts incoming connections on that endpoint. See endpoint next for details.

zmq.connect() connects the socket to a remote endpoint and then accepts outgoing connections on that endpoint. See endpoint next for details.

endpoint is a string consisting of a transport :// followed by an address. The transport specifies the underlying protocol to use. The address specifies the transport-specific address to bind to. pbdZMQ/ZMQ provides the following transports: ll{ Transport Usage tcp unicast transport using TCP ipc local inter-process communication transport inproc local in-process (inter-thread) communication transport pgm,epgm reliable multicast transport using PGM } *** warning: epgm is not turned on by default in the pbdZMQ's internal ZeroMQ library. *** warning: ipc is not supported in Windows system.

zmq.setsockopt() is to set/change socket options.

zmq.getsockopt() is to get socket options and returns option.value.

References

ZeroMQ/4.1.0 API Reference: http://api.zeromq.org/4-1:_start

Programming with Big Data in R Website: http://r-pbd.org/

See Also

zmq.ctx.new(), zmq.ctx.destroy().

Examples

### Using request-reply pattern.

### At the server, run next in background or the other windows.
library(pbdZMQ, quietly = TRUE)

context <- zmq.ctx.new()
responder <- zmq.socket(context, .pbd_env$ZMQ.ST$REP)
zmq.bind(responder, "tcp://*:5555")
zmq.close(responder)
zmq.ctx.destroy(context)


### At a client, run next in foreground.
library(pbdZMQ, quietly = TRUE)

context <- zmq.ctx.new()
requester <- zmq.socket(context, .pbd_env$ZMQ.ST$REQ)
zmq.connect(requester, "tcp://localhost:5555")
zmq.close(requester)
zmq.ctx.destroy(context)